In-vitro diagnostics (IVD) allows labs to assist in the diagnosis of disease based on assays performed on patient fluid samples. IVD includes various types of analytical tests and assays related to patient diagnosis and therapy that can be performed by analysis of a liquid sample taken from a patient's bodily fluids, or abscesses. These assays are typically conducted with automated clinical chemistry analyzers (analyzers) onto which fluid containers, such as tubes or vials containing patient samples have been loaded. The analyzer extracts a liquid sample from the vial and combines the sample with various reagents in special reaction cuvettes or tubes (referred to generally as reaction vessels). In some conventional systems, a modular approach is used for analyzers. A lab automation system can shuttle samples between one sample processing module (module) and another module. Modules may include one or more stations, including sample handling stations and testing stations (e.g., a unit that can specialize in certain types of assays or can otherwise provide testing services to the larger analyzer), which may include immunoassay (IA) and clinical chemistry (CC) stations. Some traditional IVD automation track systems comprise systems that are designed to transport samples from one fully independent module to another standalone module. This allows different types of tests to be specialized in two different stations or allows two redundant stations to be linked to increase the volume of sample throughput available.
In some conventional systems, individual carrier mechanisms (carriers), sometimes called pucks, or racks of containers are shuttled between different stations. Samples may be stored in sample containers, such as test tubes, that are placed into a carrier by an operator or a place and pick device for transport between stations in an analyzer along the track. The place and pick device is used to unload individual test tubes from the carriers to the tube storage area and load individual test tubes from a tube storage area onto the carriers. A discrete “place” operation is performed when the place and pick device loads (places) a tube from storage onto the carrier. A discrete “pick” operation is performed when the place and pick device removes (picks) a tube from a carrier and transports the tube to storage.
The place operation and pick operation may be combined into a single combined place and pick operation. That is, the place and pick device may perform a combined place and pick operation by placing a tube onto the carrier and then picking another tube from an adjacent carrier before transporting the picked tube to storage and returning to place a retrieved tube from storage onto the adjacent carrier. The adjacent carrier must, however, wait until the place and pick device returns from storage with the retrieved tube from storage before it can move toward its next destination. For this reason, some conventional systems experience sample handling queues at place and pick devices. Accordingly, one or more carriers must wait in the sample handling queue during the time required for the place and pick device to transport a picked tube from a carrier to storage and place a retrieved tube from storage onto a carrier.